I don't know what you mean by 'Drop'.
If you mean 'Give bounty gold reward', then you should change 'Stats - Bounty Gold Reward (Base)' for every unit that's used to be owned by Teal player, in Object editors.
If you really mean 'Drop' as an item, go create a new item based on 'Gold' item in Object Editor, when someone kills the unit, drop from him the item that you created in Object editor. In another trigger, make that when a hero/unit acquires the item, give him Gold and remove acquired item.